How Did Rome's Military Conquests Create Strains on the Military

How did Rome's military conquests create strains on the military?

A) The Roman military was stretched so thin that it was required to draft slaves and those in poverty to fill out the legions.
B) The military suffered a large number of casualties over the years and lacked adequate facilities for their care and support.
C) The military had grown to such proportions that it could no longer be fed and supplied adequately by the Roman people.
D) Rome's Italian allies had carried much of the burden of fighting but had received fewer rewards than the Roman officers and soldiers.